I just put an app called Lemon Wallet on my iPhone 5 and I really like it.

Basically, what you do is take all of your cards out of your wallet (credit cards, membership cards, identification cards, etc.) and take a picture of them from inside the app. The app digitizes each card and fills in fields for you.

The outcome is a nicely organized list of all your cards. When you click on the card you want, it simulates pulling it out of your wallet and then gives you a nice picture of the front and back along with the digitized information.

It can export the info to the new Passbook app if you want to, but I really don't see the need.

If you want to try Lemon Wallet on your iPhone, it's in the Apple App Store for free.